I see a couple of different "issues" here. One, this teacher has good structure and appears to move well while maintaining structure. This, to me, is a hallmark of developing and utilizing good energy. Two, his students have taken to amplifying the effects of experiencing energy. This is a martially moronic thing to do. It would have been better to have seen them try and "ground out" the energy or at least, maintain their structure and creating safe distance. Three, his students are taking ukemi, as opposed to not having a choice in the matter. Four, I would like to see this teacher handle a well-trained martial artist employing sincere and effective attacks. I am not suggesting that this teacher would not be able to respond effectively, but I would be curious to see what that video clip would look like.